not sure what the battery life on x230 is. I usually get 6-7 hours atleast on my current chromebook.
Besides this was an impulse purchase. I was tired of my home laptop and wanted something so I went to best buy and purchased it within half an hour. I can't say the same for x230.
With the 9 cell I get easily 15 hours while developing. Not sure which Chromebooks you are talking about. But I prefer the x220 over the 230. Haven't tried the 240 which is now starting to get cheap second hand here.
This is not my primary machine however. I only use it at home to ssh into my desktop once in a while.